microstructure of metal materials
DESCRIPTION
Microstructure of Metal Materials Data baseTRANSCRIPT
Metal specimen set
Metallurgical Studyfor
TIS MOTION & CONTROL PTE LTENO 63 UBI AVENUE 1, #03-01,PAYA UBI INDUSTRIAL PARK
SINGAPORE 408934.Tel.: 741 5995 Fax: 741 6656
The microstructures can tell the properties, quality, and the characteristics of metals. Metals with different compositions and different heat treatment condition will be different in microstructures. These set ofspecimens contains various kinds of ferrous metal in various conditions. These specimens can be used as thereference in studying of Metallurgy, Foundry, Heat Treatment, and Manufacturing Processes, etc.
There are 30 pieces of specimen in this set. Each specimen is prepared, etched, and coated withtransparency coating material to protect the specimen surface and to be able to be seen under microscope.without any cleaning process. The specimens were kept in three wooden boxes, 10 pieces each. The data andspecimen descriptions and micro-photographs are prepared and combined as a book and supplied together with the specimens.
TIS MOTION & CONTROL PTE LTD
Preface
1. General background and Introduction ………………………. 1-72. Carbon steels 2.1 Low carbon steel …………………………………………… 8-15 2.2 Medium carbon steel ……………………………………. 16-21 2.3 High carbon steel …………………………………………….. 22-293. Low alloy steels 3.1 AISI 4130 steel …………………………………………………. 30-33 3.2 AISI 4340 steel …………………………………………………. 34-354. Cast irons 4.1 Gray cast iron …………………………………………………. 36-41 4.2 White cast iron …………………………………………………. 42-43 4.3 Malleable iron ……………………………………………….. 44-45 4.4 Nodular cast iron ……………………………………………….. 46-49 4.5 Bainitic Ductile Iron ( BDI) ……………………………………. 50-51 4.6 Wear resistant cast iron(Alloy cast iron) ……………………. 52-535. Tool steels 5.1 High carbon high chromium tool steel ( AISI D2 ) ………….. 54-57 5.2 Mold tool steel (AISI P 20 ) ……………………………………. 58-61 5.3 High speed steel …………………………………………..….. 62-636. Cast steel 6.1 High manganese steel ……………………………………. 64-67
Contents
1.General Background and Introduction
1.1 General Engineering Materials:
Engineering materials can be classified into two classes, Metal and Non-metal.
A Metal: an element that has several metallic properties as the followings:1. Shiny appearance.2. Give sonorous tone when struck.3. Good conduction of heat and electricity.4. High malleablity(can be rolled or pressed into shape).5. High ductility(can be drawn into wire).6. With possible emission of electrons when heated(thermionic effect) or when the surface is struck by light(photoelectric effect).7. Hard and heavy.8. Not transparent.
All metals have some of these properties. Some metals have every one of these properties.There are about 70 elements are classified as metals: e.g. Fe, Cr, Ni, Mg, Al, Cu etc.
A Non-metal: an element with certain physical and chemical properties opposite to those of metalsNon-metals accept electron to form negatively charged ions.
There are about 20 elements are classified as metals: e.g. S, P, C, Si and F etc.
The metals can be devided into two classes: Non-ferrous metals and Ferrous metals which arealso devided into many sub-classes as shown in Fig.1.
The Non-metals are Polymers and Ceramic are out of the scope of this book.
All specimens mentioned in this book are Ferrous metals and picked up from Carbon steels, Lowalloy steels, Cast irons, Tool steels, and Cast steels.
1.2. Steel Making
Carbon steels, Low alloy steels, and Tool steels are made as shown in Fig.2. Cast irons and Caststeels are made as shown in Fig.3.
1.3. Specimen Selection
The specimen were cut from the specified round bars and flat bars of Carbon steels, Low alloy steels, and Tool steels and heat treated according to the specified processes.
The specimen of Cast iron(gray cast iron, nodular iron, and Bainitic Ductile Iron)were casted by using induction furnace and sand mold, then heat treated according to the specified processes.
Specimen No.29,30 are special alloy cast steel, also were casted in the induction furnace withhigh percentage of Mn addition and good quality control. No.29 is in as cast condition and No.30 is afterannealing.
1.4. Specimen preparation
Every specimen was prepared according to the processes shown in Fig.4.
1.5. Heat treatment processes
General heat treatment processes are shown in Fig.5 and the heat treatment processes applied foreach specimens is shown in each data sheet for each specimen.
1
Steels
Polymer Ceramic Cast steel Spec.#29,30
Rubber General High-Mn Ceramic carbon
Plastic Spec.#18 Carbon steel steelEnginnering
Ceramic Spec.#20,21
Malleable iron Low-C steel
Spec.#19 0.05-0.30CSpec.#1 to 4Alloy steel
Graphite Graphitefree bearing
Pearlitic Martensitic High-Cr iron Acicular Spec. #12 to 14white iron white iron 11-28%Cr High strength
Wear resistant Wear resistant Wear, corrosion, wear resistantand heat resistant
Spec.#23 AusteniticTool steel
18%NiNi-resist Carbon tool
Heat and corrosion resistant Heat and corrosion resistant steel(W)
Ferritic Spec.#24,25 Spec.#26,27 Spec.#28
Austenitice.g.304,316
Alloy structural steel
heat resistant corrosion resistant
Machineries steel
Rephoshorized and Resulfurized carbon steel
Structural Steel
Spec.#8 to 11
Stainless steel
Carbon structural steel
e.g. Spring steel, Silicon steel, Heat resisting steel, Magnetic steel, Corrosion resisting steel
Austenitic Ductile Iron(ADI)
Bainitic Ductile Iron(BDI)
Spec.#22
18% Ni, 5%SiNicrosilal
High,15%, Si iron5% Si iron(Silal)
Ferrous Metals
General Enginnering Materials
Non-Ferrous MetalsMetals e.g. Copper, Aluminum, and its alloys; Super-alloys etc.
Gray cast iron
Cast Iron
Wrought steel
Spec.#5 to 7
Spec.#15 to 17Mottled cast iron
White cast iron
Ductile cast iron
Alloy cast iron
CompositMaterial
Non-resulfurizedcarbon steel
Resulfurizedcarbon steel
Ultra-high-Csteel,1-2%C
Med. C steel0.30-0.60C
High-C steel0.60-1.00C
Low and mediumalloy steel
High alloysteel
Ultra-highstrength
steel
High StrengthLow Alloy
Steel(HSLA)
Other alloysteel
e.g.Mara-ging steel
Shock re-sisting toolsteel (S)
High speedsteel(T,M)
Cold Worktool steel(A,O,D)
Mould toolsteel (P)
Hot Worktool steel
(H)
Specialpurposetool steel
(L)
Martensitice.g.410,440
Ferritic e.g.430, 439
Precipitationhardening, PH
Fig. 1: Classification ofgeneral engineering
materials. Other steels
Non-Resulfurizedcarbon steel
Resulfurizedcarbon steel
Rephosphurized andresulfurized carbon steel
High -manganesecarbon steel
2
ORES
DIRECTREDUCTION
PELLETSELECTRICFURNACE
LIME STONESINTER LADLE METALLURGY
Note: Ladle Metallurgy isused to control condition within the ladle to improveproductivity in precedingand subsequench pro-cessing steps and thequality of the final productThese conditions can
CRUSHED include temperature, pressure, chemistry, and
COAL OXYGEN momentum through stirring
SLAG
Note: A modification of the BOP is the Q-BOPwhich the oxygen and other gas are
From iron ores, lime stones, and coal blown in from the bottom rather thanin the Earth's crust to space-age steel the top as shown.this flowline shows the major steps MERCHANTin an steel making processes. PIG IRON CASTING
BLAST FURNACEMOLTEN IRONCOKE OVENS
FURNACEOPEN HEARTH
DIRECTREDUCTION
MERCHANTPIG IRON CASTING
FLUX
SCRAP
BASIC OXYGEN FURNACEOR Q-BOF
Fig.2 Steel making processesFig.2 Steel making processes
3
Molten steel must solidify SKELPbefore it can be made intofinished products in aninfinite variety, consideringchemistry, properties, and sizes. PLATE Flat rolled products
are rolled from slabs by using sets of cylin- drical rolls.
TEMPERGrooved rolle squeeze billets ROLLING
into different cross-sections(round,angles, etc.) in a sequench of operations.
RODS WIRE
TUBE ROUNDPiercing is the process used to make seam-less pipe and tube.
Note:A smal but significant percentage ofheated ingot steel is squeezed in Set of grooved rolls are used to forging presses to make large shaft to roll brooms into heavy beamfor power plants, nuclear plants, for construction or for rails.nuclear plant components, and otherproducts.
HOT FORGING
CONTINUOUS CASTING
STEEL PLATES
COLD STRIP
BLOOM
BILLET
SLAB
SEAMLESS PIPE
COLD DRAWN BARS
GALVANIZED AND OTHER COATEDFLAT ROLLED
PRODUCTS
CONVENTIONAL INGOTTEEMING
INGOT BREAKDOWNMILL
SLAB
BILLET
HOT STRIP
PLATE
HOT ROLLED BAR
TUBE ROUND
RAILS
STRUCTURALSHAPES
WELDED PIPE
COLD STRIP
Fig.2 Steel making processes, cont.
4
Pig iron
Flux
ScrapsMELTING IN INDUCTIONFURNACE
CASTING
RAW MATERIALS
PATTERN MAKING
POURING MOLTEN
MOLTEN METAL IS POUREDINTO THE LADLE
TO MOLD
MOLDING SAND PREPARATION
MOLD MAKINGMETAL FROM LADLE
HEAT TREATMENT
DESGN & DRAWING Fig. 3 Casting processes
5
1.Cutting 2.Mounting 3.Grinding 4.Polishing 5.Etching 6.Examination 7.Micro-photographycoolant coolant sand paper coolant polishing medium(Al2O3 suspension) ccd camera
specimen specimen etchant specimen specimencutting wheel
specimen grinding polishing polishing wheel cloth wheel metallurgical microscope
fixed piston
cut specimen movingpiston bekalite
specimen1.Equipment: 1.Equipment: 1.Equipment: 1.Equipment: 1.Equipment: 1.Equipment: 1.Equipment: Lab cut-off machine Hot mounting machine Grinding machine Polishing machine Watch glass Metallurgical microscope, Computer, printer.2.Cut-off wheel: 2.Resin type: 2.Grinding medium: 2.Polishing medium: 2. Quenchant: CCD camera, and Resin bonded, both soft Phenolic resin(Bekelite) Water proof sand paper Polishing cloth and water 2.1 Reagent 7a. specimen leveller.type(for hard specimen) or Acrylic resin(transpa- grit No.240,400,800,1200, suspended Alumina 2.2 Nital 3 % 2.The magnification:and hard type(for soft lent type) and 2400 powder, 0.3 micron 3.Etching time: 50x,100x, 200x, 500x.specimen) 3.Temperature: 3.Coolant: 3.Coolant: 15-30 seconds and 1000x.3.Coolant: 170-180oC Water Water 4.Cleaning:Water mixed with cooling 4.Time: Note: Note: After etching, themedium and anti-bacteria 8-12 min. The grinding must start Before polishing, the specimen must be rinsedsolution. 5.Coolant: from the coarse sand specimen and hands with flowing water andNote: Water paper and change to must be clean. washed with alcohol and The specimen must be Note: finer sand paper. During the polishing, the immediately blown with well selected and may be The mounted specimen Before changing to the specimen must be kept hot air.round square or other must be marked carefully finer sand paper, the clockwise, and counter- Note:irregular shape. to avoid confusing. grinding line from the clockwise to prevent 1. Nital 3%: The cutting must be previous sand paper comet tail. Nitric acid(HNO3): 3 cccarried out carefully and must be disappeared and The water must be used Alcohol: 97 ccenough coolant to the new grinding lines together with the polishing 2. Reagent 7a:prevent overheating must be in the same powder. 3 g potassium metabi-during cutting. direction. And before After polishing, the sulfite
starting the new sand specimen must be rinsed 1 g sulfamic acidpaper, the specimen and with water and alcohol 100 ml. Distilled waterhands must be clean. and dry with hot air. ( Reagent 7a is for color etcch )
watch glasscomputer setand printer(Keep the specimen
moving during etching)
Specimen preparation
Fig. 4 Specimen preparation
6
Gas phase deposition
Softening Hardening
Annealing Normalizing
Batch annealing Peening
Rolling
PressureSub-critical polishingannealing
Stress relieving
HEAT TREATMENT PROCESSES
Surface Treatment
Phase un-changePhase change
Full Treatment
Processannealing
Supercritical orfull annealing
Continuousannealing
Intermediatannealing
Austempering
Quench & temper
Martempering
Solution treatment & aging
Sub-zero treatment
Application of coatingInfluence on surface layer
Compositionchanges
Compositionun-changes
Mechanicalmethod
Flamehardening
Inductionhardening
Hardening by high energy heatingElectron beam hardening, etc.
Thermo-chemicalmethod
CarbonitridingCarburizing Nitriding Nitrocarburizing
PVD Coating
CVD Coating
Mechanicalmethod
Thermalmethod
Thermalmethod
Thermo-mechani-cal
method
Clading
Sintering
CurrentlessNi-deposition
Explosioncoating
Spraycoating
Tin plating
Fusion
Tin plating
Built-upwelding
Lead plating
Spark workhardening
Nickel plating
Chemicalmethod
Electrochemical method
Chromium plating
Hard facing
Copper platingSpheroidizing
Carbon© isadded(diffused
) throughsteel surface
Solid carbu-rizing (Packcarburizing)C- sources:
Carbongranulates
Vacuum carburizingC- sources:Hydrocarbon gas
CyanidingC- sources:Cyanide salt
Liquid carburizing (Salt bath carburizing)C- sources: Cyanide salt
Gas carburizingC- sources:Carbon rich atmosphere
Plasma(Ion) carburizingC-sources: Hydrocabon gas
Nitrogen(N) isadded(diffused
) throughsteel surface
Pack nitridingN-sources:
Nitrogen bearingorganic compound
Gas nitridingN-sources:Ammonia gas(NH3)
Plasma(Ion) nitridingN-sources:Ammonia gas or N2-gas
Definition:Carbon© is added to steel surface duringnitriding, but the actual process is to add nitrogen (fromNH3) to steel during carburizing process, modified from
Gas carburizing process.
High temperaturecarbonitriding
The process is doneat 900-950oC
Low temperaturecarbonitriding
The process is doneat 540-560oC
Medium temperaturecarbonitriding
The process is doneat 840-860oC
Definition:Nitrogen is added to steel surface during carburizing, butthe actual process is to add carbon and nitrogen to steel surface to
produce surface enrichment in nitrogen(N) and carbon(C)
Ferritic NitrocarburizingTo add N and C to steelsurface at temperaturewithin the ferrite phase
field, usually 570oC
AusteniticNitrocarburizing
The process is done inthe austenite phase field
Plasma NitrocarburizingThe nitrocaburizing using
glow dischargetechnology
Fig. 5 Heat treatment processes7
SpecimenNo.: 1
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.18-0.23 0.15-0.35 0.30-0.60 0.04 max 0.04max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1020 A29:1020 1.0402 - CC20 20 20 1450 S20C 3CD20 CS1020Characteristics: Most wildly used of several grade s containing about 0,20%carbon. Available in a variety of product forms. Excellent forgability and weldability. No preheating and post heating required before or after welding. Machinability is notably poor. Wildy used as a carburizing steel.Applications: Parts for case hardened condition where core strength is not critical, and shaft for large section that are not highly stressed, case hardened gears pins and chain.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 200-250 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.55-60 HRC 55-60 HRC
Final heat treatment oC 870 furnace cool Process: The specimen is heated to 880oC for 60 min., the steel microstructures will transform toprocess of this preheat 500 60 austenite, then cooldown slowly in the furnace austenite will transform to ferrite and pearlite. The steel specimen 30 min. min. The steel will be softened,better machinability,better cold workability,and improve dimensional stability,etc
100xPhoto.1: 200x,Microstructures consist of Ferrite(yellow, blue, and purple), and Pearlite Photo.2. 1000x, same as in Photo. 1 but higher magnification. Brown area can be clearly(brown), small black dots are inclusions remain in steel. seen Cementite and Ferrite in Pearlite. Grain boundaries are also clearly seen.
and no alloying element
BSBS970:040A20
UK
Specimen name Material ConditionFerrous Metal Low Carbon Steel Annealed
USA
Normalizing Through hardening Carburizing
GERMANY
Hardness
depend on case depth.
Carbonitriding925 Because of low carbon 850-870870-955
oil60-62 HRC
1/2hr./25 mm.+1 hr. depend on case depth.
Microstructures
air or nitrogen Through hardening is not oil120-130 HB advisable. 60-62 HRC
Record of Microstructures
grainboundary
Ferrite
Pearlite
8
Photo.3: 1000x, Same as in Photo.1,2 but in large area. The microstructures consist of Ferrite(blue, green, purple, yellow) and Pearlite(brown area with Cementite strips on Feerite).
9
SpecimenNo.: 2
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.18-0.23 0.15-0.35 0.30-0.60 0.04 max 0.04max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1020 A29:1020 1.0402 - CC20 20 20 1450 S20C 3CD20 CS1020Characteristics: Most wildly used of several grade s containing about 0,20%carbon. Available in a variety of product forms. Excellent forgability and weldability. No preheating and post heating required before or after welding. Machinability is notably poor. Wildy used as a carburizing steel.Applications: Parts for case hardened condition where core strength is not critical, and shaft for large section that are not highly stressed, case hardened gears pins and chain.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 200-250 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.55-60 HRC 55-60 HRC
Final heat treatment oC 920 air cool Process: The specimen is heated to 920oC for180 min.in atmosphere controlled furnace with carbonprocess of this preheat 500 180 potential o.9%. Carbon atom will diffuse into the specimen surface and combind with Fe to form Fe3C orspecimen 30 min. min. cementite in surface area, so pearlite increases in the surface area.
Photo.4: 100x, The photo was taken from surface to core of the specimen. At the Photo.5: 1000x, At the carburized surface of the specimen, the original strucutre aresurface, the microstructure become Pearlite because of increasing carbon. Ferrite and Pearlite , now no more free Ferrite because of carburization.
60-62 HRC
Microstructures
Hardness 120-130 HB advisable. 60-62 HRCair or nitrogen Through hardening is not oil oil
1/2hr./25 mm.+1 hr. and no alloying element depend on case depth. depend on case depth.
Carbonitriding925 Because of low carbon 870-955 850-870
Normalizing Through hardening Carburizing
Specimen name Material ConditionFerrous Metal Low Carbon Steel Carburized
UKUSA GERMANYBS
BS970:040A20
Record of Microstructures
surface
10
Photo. 6
Photo.7 Photo.8 Photo.9The original microstructures of the steel are Ferrite and Pearlite. After carburization, carbon diffused through the surface to the core. The structure at the surface becomes
Pearlite which consists of Cementite, Fe3C, and Ferrite (see Photo.7). Below the surface, the strucutres consist of Pearlite and Ferrite(see Photo.8) and at the core, the structures areunchanged, it still be Pearlite and Ferrite as in the original condition(see Photo.9).
11
SpecimenNo.: 3
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.18-0.23 0.15-0.35 0.30-0.60 0.04 max 0.04max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1020 A29:1020 1.0402 - CC20 20 20 1450 S20C 3CD20 CS1020Characteristics: Most wildly used of several grade s containing about 0,20%carbon. Available in a variety of product forms. Excellent forgability and weldability. No preheating and post heating required before or after welding. Machinability is notably poor. Wildy used as a carburizing steel.Applications: Parts for case hardened condition where core strength is not critical, and shaft for large section that are not highly stressed, case hardened gears pins and chain.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 200-250 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.55-60 HRC 55-60 HRC
Final heat treatment oC 920 oil quench Process: The specimen is heated to 920oC for180 min.in atmosphere controlled furnace with carbonprocess of this preheat 500 180 250 air cool potential o.9%. C atom diffused into specimen surface and combinded with Fe to form Fe3C(Cementite)specimen 30 min. 120 min. which gives more pearlite and less ferrite. After hardened and tempered, pearlite and ferrite transformed
to austenite and then martensite accordingly.Tempered martensite+P+F will be achieved finally.
Photo.10: 50x,The specimen was carburized, quench, and tempered. Pearlite at the sur- Photo.11: 1000x, At the case area, the acicular or needle like structure(Martensite) will face and below surface transformed to Martensite(left, colorfull area) be seen( purple, green, and brown).
Microstructures
60-62 HRC
MaterialLow carbon steel
ConditionCarburized, quenched and tempered
BS970:040A20
Hardness 120-130 HB advisable. 60-62 HRCair or nitrogen Through hardening is not oil oil
1/2hr./25 mm.+1 hr. and no alloying element depend on case depth. depend on case depth.925 Because of low carbon 870-955 850-870
Normalizing Through hardening Carburizing Carbonitriding
USA GERMANY UKBS
Specimen nameFerrous MetalRecord of Microstructures 12
Photo.13 1000x Photo.14 1000x Photo.15 1000xPhoto.12 shows the microstructures from the surface of low carbon steel to the core after carburized, quenched, and tempered. The case with green, purple, and yellow
is Martensite(see Photo.13). Between case and core are Martensite and Ferrite(see Photo.14). At the core, the microstructures remain the same as the original, Pearlite and Ferrite, somePearlite may transfer to Martensite, but Ferrite still unchanged(see Photo.15).
13
Photo.12,50x
SpecimenNo.: 4
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.18-0.23 0.15-0.35 0.30-0.60 0.04 max 0.04max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1020 A29:1020 1.0402 - CC20 20 20 1450 S20C 3CD20 CS1020Characteristics: Most wildly used of several grade s containing about 0,20%carbon. Available in a variety of product forms. Excellent forgability and weldability. No preheating and post heating required before or after welding. Machinability is notably poor. Wildy used as a carburizing steel.Applications: Parts for case hardened condition where core strength is not critical, and shaft for large section that are not highly stressed, case hardened gears pins and chain.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 200-250 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.55-60 HRC 55-60 HRC
Final heat treatment oC 850 oil quench Process: The specimen is heated to 850oC for180 min.in atmosphere controlled furnace with carbonprocess of this preheat 500 180 250 air cool potential o.9%and some of NH3 gas.C and N atom will diffuse into specimen surface and form both cemen-specimen 30 min. 120 min. tite and nitride compounds in surface area.After quenched and tempered, tempered martensite+nitride+
pearlite+ferrite will be achieved.
Photo.16: 50x, Cross-sectioned shows the microstructures from surface to core of Photo.17: 1000x, Photo taken at the case, needlelike structure, Martensite.the specimen. Dark case is Martensite, colorfull core are Pearlite and Ferrite.
60-62 HRC
Microstructures
Hardness 120-130 HB advisable. 60-62 HRCair or nitrogen
1/2hr./25 mm.+1 hr. and no alloying element depend on case depth. depend on case depth.870-955 850-870
Through hardening is not oil oil
UKBS
BS970:040A20
Normalizing Through hardening Carburizing Carbonitriding
GERMANY
ConditionFerrous Metal Low carbon steel Carbonitrided, hardened and tempered
925 Because of low carbon
Specimen name Material
USA
Record of Microstructures 14
Photo.18 shows the microstructures from the surface to the core of low carbon steel after carbonitrided, quenched and tempered. The case consists of Martensite(seePhoto.19). Between the case and core, consists of Martensite and Ferrite(see Photo.20). And at the core, the original microstructures, Pearlite and Ferrite still remain(see Photo.21).
:Photo.19:500x Photo.20:500x Photo.21:500x
Photo.18:50x
15
SpecimenNo.: 5
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.50-0.60 0.15-0.35 0.60-0.90 0.04 max 0.045max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1055 A29:1055 1.1209,CM55 CM55 CX55 55 55 1665 S53C 3CD55 K1055Characteristics: When heat treated, this steel yield a high surface hardness, combinded with relative good toughness. This grade also has good forging characteristics. It isshallow hardening, however, and useful section size is limited. Part made from AISI1055 steel requiring strength are oil quenched; parts requiring high hardness are water quench.Applications: Battering tools, hot upset forging dies, ring rolling tools, wear resistant parts, hand tools, and parts for agricultural imprements with high strength and low cost.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-450 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.60-40 HRC 60 HRC
Final heat treatment oC 830 furnace cool Process: The specimen is heated to 830oC, soaking time should be at 1/2 hour per inch of thicknessprocess of this preheat 500 plus 1 hour minmum and furnace cool to 650 oCat a rate not exceed 28 oC per hour. Microstructuresspecimen 30 min. min. consist of pearlite and ferrite. Low hardenability, good forgability, poor machinability, not recommend for
welding.
Photo.22: 100x, Medium carbon steel,annealed, consists of Pearlite and Ferrite. Photo.23: 1000x,Same as Photo.22, but in higher magnification. Light brown and brown area are Ferrite, green and purple area with small lines are Pearlite.
60-62 HRC
Microstructures
Hardness 180-200 HB 197 HB 60-64 HRCair or nitrogen furace cool oil or water oil
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. depend on case depth. depend on case depth.900 830 830 850-870
En55
Normalizing Annealing Full hardening Carbonitriding
USA GERMANY UKBS 1429
Specimen name Material ConditionFerrous Metal Medium carbon steel AnnealedRecord of Microstructures 16
Photo.24: 500x, Same as in Photo.23, but in the larger area.The microstructures consist of Pearlite and Ferrite.
17
SpecimenNo.: 6
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.50-0.60 0.15-0.35 0.60-0.90 0.04 max 0.045max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1055 A29:1055 1.1209,CM55 CM55 CX55 55 55 1665 S53C 3CD55 K1055Characteristics: When heat treated, this steel yield a high surface hardness, combinded with relative good toughness. This grade also has good forging characteristics. It isshallow hardening, however, and useful section size is limited. Part made from AISI1055 steel requiring strength are oil quenched; parts requiring high hardness are water quench.Applications: Battering tools, hot upset forging dies, ring rolling tools, wear resistant parts, hand tools, and parts for agricultural imprements with high strength and low cost.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-450 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.60-40 HRC 60 HRC
Final heat treatment oC 830 Process: The specimen is heated to 830oC, pearlite and ferrite transformed to austenite, someprocess of this preheat 500 60 water quench cementite remained, and then quenched in water, austenite then transformed to martensite.The martensite specimen 30 min. min. is untempered martensite, high stess, high hardness, brittle, not suitable for any application. Some Ferrite
retained because of low hardenability of steel.
Photo.25: 100x, Medium carbon steel, heated to 830oC and quenched in water, micro- Photo.26: 1000x, Green,purple and blue area are Martensite, bright gray area are Ferrite.structures consist of Martensite and some Ferrite still remain because of low hardenability.
60-62 HRC
Microstructures
Hardness 180-200 HB 197 HB 60-64 HRCair or nitrogen furace cool oil or water oil
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. depend on case depth. depend on case depth.900 830 830 850-870
UKBS 1429
En55
Normalizing Annealing Full hardening Carbonitriding
Specimen name Material ConditionFerrous Metal Medium carbon steel Hardened by quenching, untempered
USA GERMANY
Record of Microstructures 18
Photo.27: 1000x, Same as in Photo.26, but in larger area. The microstructures consist of Martensite and un-changed Ferrite.
19
SpecimenNo.: 7
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.50-0.60 0.15-0.35 0.60-0.90 0.04 max 0.045max - - - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
1055 A29:1055 1.1209,CM55 CM55 CX55 55 55 1665 S53C 3CD55 K1055Characteristics: When heat treated, this steel yield a high surface hardness, combinded with relative good toughness. This grade also has good forging characteristics. It isshallow hardening, however, and useful section size is limited. Part made from AISI1055 steel requiring strength are oil quenched; parts requiring high hardness are water quench.Applications: Battering tools, hot upset forging dies, ring rolling tools, wear resistant parts, hand tools, and parts for agricultural imprements with high strength and low cost.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-450 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air air mended.60-40 HRC 60 HRC
Final heat treatment oC 830 Process: The specimen is heated to 830oC, pearlite and ferrite transformed to austenite, and thenprocess of this preheat 500 60 300 quenched in water, austenite then transformed to martensite.The as quench martensite is hard and specimen 30 min. 120 min. brittle. The specimen was tempered at 300oC for 120 minutes, martensite transformed to tempered mar-
tensite with lower hardness, higher toughness. The hardness can be controlled by varying temperature.
Photo.28: 100x, Medium carbon steel, quenched and tempered, microstructures consist Photo.29: 1000x, Same as in Photo.28, but in higher magnification. Tempered Martensite of tempered Martensite, smaal dark dots are inclusions in steel. are clearly seen.
60-62 HRC
Microstructures
Hardness 180-200 HB 197 HB 60-64 HRCair or nitrogen furace cool oil or water oil
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. depend on case depth. depend on case depth.900 830 830 850-870
En55
Normalizing Annealing Full hardening Carbonitriding
USA GERMANY UKBS 1429
Specimen name Material ConditionFerrous Metal Medium carbon steel Hardened by quenching and temperingRecord of Microstructures 20
Photo.30: 1000x, Same as in Photo.29, but in larger area. The microstructures consist of tempered martensite.
21
SpecimenNo.: 8
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.90-1.03 0.15-0.35 0.30-0.50 0.04 max 0.050max - - - - - - - -
Similar FRANCE INDIA POLAND SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR IS 1570 PN84028 SS14 JIS G4801 UNI3545 AS1442
1095 A510;A586 1.1275 - CX100 C98 DS105 1870 SUP 4 C100 K1095Characteristics: The higher carbon of 1095 steel provides maximum surface hardness with improved wear resistance and high strength. Ther is, however, a loss of tough-ness. Because cold forming methods are not suitable for this steel, uses are limitted to flat stampings and springs coiled from small diameter wire.Applications: Edge tools, wear-resistant parts, mower knives, scraper blades, discs, etc.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Final heat treatment oC 870 furnace cool Process: The specimen is a hyper- eutectoid steel. The specimen was reheated to 800 oC for 60 min.process of this preheat 500 60 for austenitizing, then slowly cooled down the specimen in the furnace at the cooling rate not exceed specimen 30 min. min. 28oC per hour until 650oC then air cooled to room temperature. The final microstructure are pearlite and
carbide. If the surface is not well protected, carbon content will decrease(decarburization).
Photo.31: 100x, The microstructures consist of Pearlite and carbides Photo.32: 1000x,Same as in Photo.31, but in higher magnification. The matrix is Pearlite.white particles are carbides or Cementite, Fe3C.
air
Microstructures
Hardness 269-290 HB 269-290 HB 63-66 HRCair or nitrogen furnace cool oil or water
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 2 hrs min.855 800 800 370-675
95CS
Normalizing Annealing Full hardening Tempering
USA GERMANY UKBS 1449
Specimen name Material ConditionFerrous Metal High carbon steel Annealed
Austempering800
1/2hr./25 mm.+1 hr.salt bath at 315 oC, 2 hrs., air cool
63-66 HRC27-43 HRC
Record of Microstructures 22
23
Photo.33:1000x, Same as in Photo.32, but in larger area. Microstrucutres consist of Pearlite matrix and Carbides particles.
SpecimenNo.: 9
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.90-1.03 0.15-0.35 0.30-0.50 0.04 max 0.050max - - - - - - - -
Similar FRANCE INDIA POLAND SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR IS 1570 PN84028 SS14 JIS G4801 UNI3545 AS1442
1095 A510;A586 1.1275 - CX100 C98 DS105 1870 SUP 4 C100 K1095Characteristics: The higher carbon of 1095 steel provides maximum surface hardness with improved wear resistance and high strength. Ther is, however, a loss of tough-ness. Because cold forming methods are not suitable for this steel, uses are limitted to flat stampings and springs coiled from small diameter wire.Applications: Edge tools, wear-resistant parts, mower knives, scraper blades, discs, etc.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Final heat treatment oC 800 water Process: The specimen was heated to 800oC for austenitizing and soaked for 60 minutes, pearliteprocess of this preheat 500 60 quench will transform to austenite, and some cementite may remain. Then quench in water, austenite will specimen 30 min. min. transform to martensite, needlelike structure, high stress, hard and brittlle. High carbon steel in this
condition is not suitable for any application because of brittleness.
Photo.34: 100x, The microstructures consist of martensite and carbides. Photo.35: 1000x, Same as in photo.34, but in higher magnification. Acicular structure isMartensite and white particles are carbides. Light blue area are retained Austenite.
Ferrous Metal High carbon steel Hardened by quenching, untemperedSpecimen name Material
USA GERMANY UKBS 1449
855 800 800
95CS
Normalizing Annealing Full hardening
2 hrs min. 1/2hr./25 mm.+1 hr.air salt bath at 315 oC, 2 hrs., air coolair or nitrogen furnace cool oil or water
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr.
Hardness 269-290 HB 269-290 HB 63-66 HRC
Microstructures
Tempering Austempering370-675 800
Condition
27-43 HRC 63-66 HRC
Record of Microstructures 24
Photo.36: 1000x, Same as in Photo.35, but in larger area. The microstructures consist of Martensite, Carbides and retained Austenite.
25
SpecimenNo.: 10
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.90-1.03 0.15-0.35 0.30-0.50 0.04 max 0.050max - - - - - - - -
Similar FRANCE INDIA POLAND SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR IS 1570 PN84028 SS14 JIS G4801 UNI3545 AS1442
1095 A510;A586 1.1275 - CX100 C98 DS105 1870 SUP 4 C100 K1095Characteristics: The higher carbon of 1095 steel provides maximum surface hardness with improved wear resistance and high strength. Ther is, however, a loss of tough-ness. Because cold forming methods are not suitable for this steel, uses are limitted to flat stampings and springs coiled from small diameter wire.Applications: Edge tools, wear-resistant parts, mower knives, scraper blades, discs, etc.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Final heat treatment oC 800 water Process: The specimen was heated to 800oC for austenitizing and soaked for 60 minutes, pearliteprocess of this preheat 500 60 300 air will transform to austenite, and some cementite may remain. Then quench in water, austenite will specimen 30 min. 120 min. transform to martensite, needlelike structure, high stress, hard and brittlle. The specimen was reheated to
300oC for 120 minutes, the hardness and brittleness will be decreased and toughness increased.
Photo.37: 100x, The microstructures consist of Martensite, and carbides. Photo.38: 1000x, Same as in Photo.37, but in higher magnification.The matrix is MartensiteWhite particles are carbides.
Specimen name MaterialFerrous Metal High carbon steel
USA GERMANY UKBS 1449
800
95CS
Normalizing Annealing Full hardening855 800 800 370-675
salt bath at 315 oC, 2 hrs., air cool1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 2 hrs min. 1/2hr./25 mm.+1 hr.
air or nitrogen furnace cool oil or water air
Microstructures
Hardness 269-290 HB 269-290 HB 63-66 HRC
Tempering Austempering
ConditionHardened by quenching, tempered
27-43 HRC 63-66 HRC
Record of Microstructures 26
Photo.39: 1000x, Same as in Photo.38, but in larger area. The microstructures consist of Martensite, and carbides.
27
SpecimenNo.: 11
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.90-1.03 0.15-0.35 0.30-0.50 0.04 max 0.050max - - - - - - - -
Similar FRANCE INDIA POLAND SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR IS 1570 PN84028 SS14 JIS G4801 UNI3545 AS1442
1095 A510;A586 1.1275 - CX100 C98 DS105 1870 SUP 4 C100 K1095Characteristics: The higher carbon of 1095 steel provides maximum surface hardness with improved wear resistance and high strength. Ther is, however, a loss of tough-ness. Because cold forming methods are not suitable for this steel, uses are limitted to flat stampings and springs coiled from small diameter wire.Applications: Edge tools, wear-resistant parts, mower knives, scraper blades, discs, etc.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Final heat treatment oC 800 furnace cool Process: The specimen is a hyper- eutectoid steel. The specimen was reheated to 800 oC for 60 min.process of this preheat 500 60 for austenitizing, then slowly cooled down the specimen in the furnace at the cooling rate not exceed specimen 30 min. min. 28oC per hour until 650oC then air cooled to room temperature. The final microstructure are pearlite and
carbide. If the surface is not well protected, carbon content will decrease(decarburization).
Photo.40: 100x, The specimen is un-etched for inclusion investigation. Black dots and Photo.41: 1000x, Same as in Photo.40, but in higher magnification. Brown particles arebrown particle are inclusion embeded in steel. non-metalic inclusion. These inclusions remained from the melting processes.
Specimen name MaterialFerrous Metal High carbon steel
USA GERMANY UK
Annealed, for inclusion investigation
BS 1449
Normalizing Annealing Full hardening
95CS
855 800 800 370-6751/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 2 hrs min.
air or nitrogen furnace cool oil or water airHardness 269-290 HB 269-290 HB 63-66 HRC
Microstructures
27-43 HRC 63-66 HRC
Tempering Austempering
Condition
salt bath at 315 oC, 2 hrs., air cool1/2hr./25 mm.+1 hr.
800
Record of Microstructures 28
Photo.42:1000x, The brown area are non-metallic inclusions.The specimen is un-etched.
29
SpecimenNo.: 12
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.28-0.33 0.15-0.30 0.40-0.60 0.035 max 0.040max 0.80-1.10 0.15-0.25 - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN17200 KRUPP AFNOR GOST4543 GB 3077 SS14 JIS G4105 UNI AS1444
4130 A29;A322 1.7218 7218 30CD4 30ChM 30CrMo 2233 SCM430 25CrMo4 4130Characteristics and applications: A medium carbon, Chromium-Molybdenum steel. Available as hot rolled and cold finished bar and seamless tube, this steel is forgeneral purpose applications. Variations in heat treatment can obtain a broad range of strength and toughness. This steel has good hardenability, strength, wear resistance, toughness and ductility. In heat treated condition, it offers good strength and toughness for moderately stressed parts.It is available in forging quality, and aircraft quality.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-650 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air or faster air mended.48-22 HRC 58-60 HRC
Final heat treatment oC 855 furnace cool Process: The specimen was heated at 855oC and soak for 60 minutes for austenitizing, the originalprocess of this preheat 500 60 microstructure will be transformed to austenite, then cooled down slowly in the furnace, austenite willspecimen 30 min. min. be transformed to pearlite and ferrite. Strength and hardness decrease, ductility increases.
USA GERMANY UK
Specimen name MaterialFerrous Metal AISI 4130
Normalizing Annealing Full hardening Carbonitriding
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr.900 855 880
45-50 HRCair or nitrogen furnace cool
60-62 HRCoil or water oil
Microstructures
Hardness 163-217 HB 217 HB
CDS110
Condition
depend on case depth.
BS 1717
Annealed
850-870
Record of Microstructures
Photo.44:1000x, Same as in Photo.34, but in higher magnification. Dark brown areaare Pearlite, light area are ferrite.
Photo.43:100x, The microstructures consist of Pearlite and Ferrite.
30
Photo.45:1000x, Same as in Photo.44, but in larger area. Light area are Ferrite, dark area are Pearlite.
31
SpecimenNo.: 13
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.28-0.33 0.15-0.30 0.40-0.60 0.035 max 0.040max 0.80-1.10 0.15-0.25 - - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5598 AS1442
4130 A510;A586 1.1259 - CX80 80 80 1778-02 S80C 3CD80 K1082Characteristics and applications: A medium carbon, Chromium-Molybdenum steel. Available as hot rolled and cold finished bar and seamless tube, this steel is forgeneral purpose applications. Variations in heat treatment can obtain a broad range of strength and toughness. This steel has good hardenability, strength, wear resistance, toughness and ductility. In heat treated condition, it offers good strength and toughness for moderately stressed parts.It is available in forging quality, and aircraft quality.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-650 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air or faster air mended.48-22 HRC 58-60 HRC
Final heat treatment oC 880 Process: The specimen was heated at 880oC and soak for 120 minutes for austenitizing, the originalprocess of this preheat 500 60 250 microstructure will be transformed to austenite, then quench in water, austenite will be transformed to specimen 30 min. 120 min. martensite, high strees, high hardness, then tempered at 250oC for 120 minutes. Martensite will be trans-
formed to tempered martensite with lower hardness and higher toughness.
60-62 HRC
Microstructures
Hardness 163-217 HB 217 HB 45-50 HRCair or nitrogen furnace cool oil or water oil
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. depend on case depth.900 855 880 850-870
80CS
Normalizing Annealing Full hardening Carbonitriding
USA GERMANY UKBS 1449
Specimen name Material ConditionFerrous Metal AISI 4130 Hardened by quenching and temperingRecord of Microstructures
Photo.46:100x, Microstructure after quenching and tempering is Martensite. Photo.47:1000x, Same as in Photo.46, but in higher magnification.The structures areMartensite.
32
200
Photo.48:500x, The microstructures are Martensite
33
SpecimenNo.: 14
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.38-0.43 0.15-0.30 0.60-0.80 0.05 max 0.040max 0.70-0.90 0.20-0.30 1.65-2.00 - - - - -
Similar FRANCE RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN KRUPP AFNOR GOST1050 GB 699 SS14 JIS UNI5332 AS1444
4340 A29: 4340 1.6582 6582 - - - 1778-02 SNCM439 40NiCrMo7 4340Characteristics and applications: A high hardenabiliy steel, higher in hardenability than other standard AISI grade. AISI 4340 steel is nickel-chromium-molybdenumalloy steel. It is normally heat treated by quenching in oil and tempering to the desired hardness. It exibits good response to heat treatment and posses a good combination of strength, ductility, and toughness in quenched and tempered condition. AISI4340 is found in aircraft and truck parts and some ordnance materials, and also for gear, shafts, die block, etc.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-650 200-250 Nitriding is guide Soaking time, min. 2 hrs min. 2 hrs min. not recom-
Quenching medium air or faster air mended.48-22 HRC 58-60 HRC
Final heat treatment oC 855 furnace cool Process: The specimen was heated at 855oC and soak for 60 minutes for austenitizing, the originalprocess of this preheat 500 60 microstructure will be transformed to austenite, then cooled down slowly in the furnace, austenite willspecimen 30 min. min. be transformed to pearlite and ferrite. Strength and hardness decrease, ductility increases.
60-62 HRC
Microstructures
Hardness 163-217 HB 217 HB 45-50 HRCair or nitrogen furnace cool oil or water oil
1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. 1/2hr./25 mm.+1 hr. depend on case depth.900 855 880 850-870
818Mo
Normalizing Annealing Full hardening Carbonitriding
USA GERMANY UKBS 4670
Specimen name Material ConditionFerrous Metal AISI 4340 AnnealedRecord of Microstructures
Photo.49:100x, Microstructures are Pearlite and ferrite. Photo.50: 1000x, Same as in Photo.49, but in higher magnification. Light area areFerrite, dark area are Pearlite. Fine bright particles are Carbides.
34
Photo.51: 500x, The microstrucutres are Pearlite and Ferrite. Fine bright particles are Carbides.
35
SpecimenNo.: 15
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 2.50-4.00 1.00-3.00 0.20-1.00 0.002-1.00 0.02-0.25 - - - - - - - -
Similar Germany RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN 1691 GOST1412 GB 699 SS14 JIS UNI5007 AS1830
- A48: 25 GG15 SCh18 - 0115.00 FC25 G15 T180Characteristics and applications: Cast irons are alloys of iron(Fe), carbon©, and silicon(Si) in which more carbon is present than can be retained in in solid solution in austenite at the uetectic temperature. The carbon that exceeds the solubility in austenite precipitates as flake graphites. Gray cast iron is used for many different types of parts in a very wide variety of machines and structures. For example: machine bed, motor housing, gear, pulley, wheel, etc.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-650 Nitriding is guide Soaking time, min. 2 hrs min. - not recom-
Quenching medium air or faster mended.48-22 HRC
Manufacturing pro- Process: The charges (consist of pig iron, cast iron scraps, steel scraps, FeSi, FeMn, flux) werecess of this specimen charged into induction furnace and melted into liquid metal, then the molten metal was dicharged into the
charge melting pouring casting crucible and then poured into prepared sand mould. Molten metal will be solidified and taken out of the sand mould. The casting was cut to specimen and ground, polished, un-etched to show graphite flakes.
Specimen name Material ConditionFerrous Metal Gray Cast Iron As cast, un-etched
USA UKBS 1452
180
Normalizing Annealing Full hardening Carbonitriding885-925 790-900 755-790 Carbonitriding of
furnace cool oil or water recommended1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. gray cast iron is not
Microstructures
FRANCEAFNOR NF A32101
FGL200G
Hardness 163-217 HB 160-180 HB 45-50 HRCair or nitrogen
Record of Microstructures
Photo.52:100x, Gray cast iron, un-etched, showing graphite flakes distribution Photo.53:1000x, Same as in Photo.52, but in higher magnification, the dark gray scripts aregraphite flakes.
36
Photo.54: 200x, Showing graphite flake distribution and orientation. Dark gray particles and scripts are graphite flakkes. The matrix is un-revealed.
37
SpecimenNo.: 16
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 2.50-4.00 1.00-3.00 0.20-1.00 0.002-1.00 0.02-0.25 - - - - - - - -
Similar Germany RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN 1691 GOST1412 GB 699 SS14 JIS UNI5007 AS1830
- A48: 25 GG15 SCh18 - 0115.00 FC25 G15 T180Characteristics and applications: Cast irons are alloys of iron(Fe), carbon©, and silicon(Si) in which more carbon is present than can be retained in in solid solution in austenite at the uetectic temperature. The carbon that exceeds the solubility in austenite precipitates as flake graphites. Gray cast iron is used for many different types of parts in a very wide variety of machines and structures. For example: machine bed, motor housing, gear, pulley, wheel, etc.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-650 Nitriding is guide Soaking time, min. 2 hrs min. - not recom-
Quenching medium air or faster mended.48-22 HRC
Manufacturing pro- Process: The charges (consist of pig iron, cast iron scraps, steel scraps, FeSi, FeMn, flux) werecess of this specimen charged into induction furnace and melted into liquid metal, then the molten metal was dicharged into the
charge melting pouring casting crucible and then poured into the sand mould. Molten metal will be solidified into solid(casting). The casting was cut, mounted, dround, polished, and etched to show both graphite flakes and matrix.
Specimen name Material ConditionFerrous Metal Gray Cast Iron As cast, etched
USA FRANCE UKAFNOR NF A32101 BS 1452
FGL200G 180
Normalizing Annealing Full hardening Carbonitriding885-925 790-900 755-790 Carbonitriding of
recommended1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. gray cast iron is not
163-217 HB 160-180 HB 45-50 HRCair or nitrogen furnace cool oil or water
Microstructures
Hardness
Record of Microstructures
Photo.55:100x, Gray cast iron, as cast, etched, showing graphite and matrix. Photo.56:1000x, Same as in Photo.55, but in higher magnification, dark scripts are gra-phite flakes, matrix are Pearlite and Ferrite.
FerritePearlite Graphite
38
Photo.57:Same as in photo.56, but in larger area. Dark gray branches are graphite flakes. The matrix consists of Pearlite(small lines of cementite and Ferrite), and Ferrite.
39
SpecimenNo.: 17
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 2.50-4.00 1.00-3.00 0.20-1.00 0.002-1.00 0.02-0.25 - - - - - - - -
Similar Germany RUSSIA CHINA SWEDEN JAPAN ITALY AUSTRALIAsteels AISI/SAE ASTM DIN 1691 GOST1412 GB 699 SS14 JIS UNI5007 AS1830
- A48: 25 GG15 SCh18 - 0115.00 FC25 G15 T180Characteristics and applications: Cast irons are alloys of iron(Fe), carbon©, and silicon(Si) in which more carbon is present than can be retained in in solid solution in austenite at the uetectic temperature. The carbon that exceeds the solubility in austenite precipitates as flake graphites. Gray cast iron is used for many different types of parts in a very wide variety of machines and structures. For example: machine bed, motor housing, gear, pulley, wheel, etc.Heat Descriptions Processes Tempering Tempering Nitridingtreatment Temperature, oC 250-650 Nitriding is guide Soaking time, min. 2 hrs min. - not recom-
Quenching medium air or faster mended.48-22 HRC
Final processes of oC w Process: The specimen was heated to 790oC for austenitizing. During austenitizing, the matrix which this specimen air consist of pearlite and ferrite, will transform to austenite, graphite flakes still remain. After soaking at the
min. temperature, the specimen was quenched in water, austenite transformed to martensite. The as quench microstructure consists of martensite and graphite. Martensite will be tempered martensite after tempering.
Specimen name Material ConditionFerrous Metal Gray Cast Iron Hardened by quenching and tempering
USA FRANCE UKAFNOR NF A32101 BS 1452
FGL200G 180
Normalizing Annealing Full hardening Carbonitriding885-925 790-900 755-790 Carbonitriding of
recommended1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. gray cast iron is not
163-217 HB 160-180 HB 45-50 HRCair or nitrogen furnace cool oil or water
Microstructures
Hardness
Record of Microstructures
790
6030060
Photo.58:100x, Gray cast iron, quenched and tempered. The matrix is Martensite.Graphite flakes still remain.
Photo.59:1000x, Same as in Photo.58, but in higher magnification. The matrix areMartensite. Gray area are graphite flakes.
40
Photo.60:1000x, Acicular structures are Martensite, dark gray scripts are graphite flakes, and the yellow and light brown surrounded the grapgite flakesare Ferrite.
41
SpecimenNo.: 18
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 1.80-3.60 0.50-1.90 0.25-0.80 0.06-0.20 0.06-0.20 - - - - - - - -
Similar USA RUSSIA CHINA SWEDEN JAPAN ITALY INDIAsteels AISI/SAE - - - - IS7925
- - - - - 1Characteristics and applications: Exhibits a white, crystalline fracture surface because fracture occures along the iron carbide plates; it is the result of metastable solidification(Fe3C eutectic). Hard and brittle. Good wear resistant. Weldability is poor. Machinability is poor. If reheated above eutectoid interval, soaked and cooled through eutecticinterval, malleable iron will be achieved. Alloying elements can be added to white iron to make alloy cast iron, e.g. Cr is added for wear resistant purpose.Heat treatment guide: Only stress relieving is recommended for white cast iron when high wear resistant is required. Stress relieving of white cast iron can be done by heatingthe parts to about 550-650 oC, soking time is 1 hour per 25 mm. of thickness and air cool. White cast iron can be hardened also to get martensite matrix but seldomly practice.Manufacturing pro- Process: Raw materials ( pig iron, scraps, ferro-alloy material, and fluxes) are put in the inductioncess of this specimen furnace and poured into prepared sand mould. The raw materials added must be calculated and weighed
charge melting pouring casting before charging into the furnace to achieve the composition required.
Specimen name Material ConditionFerrous Metal White Cast Iron As cast, etched
1AG-X300NiMo3Mg
FRANCE UKAFNOR NF A32-401 BS 4844
GermanyDIN 1695
FBO
Microstructures
Record of Microstructures
Photo.61:100x, White cast iron(hypo-eutectic cast iron), as cast, microstructures consist ofPearlite(brown and dark brown area), and Ledeburite(eutectic:Cementite and Pearlite).
Photo.62:1000x, Same as in Photo.61, but in higher magnification. Large brown islands are freePearlite which transformed from primary Austenite, small islands are Pearlite, parts ofLedeburite(eutectic). Bright area are cementite(Fe3C), parts of Ledeburite.
42
Photo.63:1000x, Same as in Photo.62, but in larger area, showing Pearlite, and Ledeburite.
CementitePearlite
43
Specimen ConditionNo.: 19 annealed
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 2.20-2.90 0.90-1.90 0.15-1.20 0.02-0.20 0.02-0.20 - - - - - - - -
Similar USA RUSSIA JAPAN ITALY INDIAsteels ASTM A220 GOST1215 JIS G5704 - IS2640
45006 KCh45-7 FCMP45 - PM440Characteristics and applications: Malleable is a type of cast iron that has most of carbon in the form of irregular shaped graphite nodules instead of flakes. Malleable iron is produced by first casting the casting as a white iron and then heat treating the white iron to convert the iron carbide into the irregularly shaped nodules of graphite. This form of graphite is called temper carbon because it is formed in the solid state during heat treatment. Malleable iron is good for making flanges, pipe fittings, valve parts for railroad, marine, etc. Heat treatment guide: Malleble iron can be hardened by the following methods: 1. First stage anneal of the casting and air cool, about 0.75% of combined carbon will remain in the matrix. 2. Reheat the casting at 885oC for 60 min. to reaustenize the matrix and homogenize the combined carbon; and then quench in heated(50-55oC) and agitated oil to form martensitewith the hardness of about 555 to 627 HB. Then temper to the required hardness. And also malleable iron can be carburized, carbonitrided, and nitrided to add surface wear resistance.Manufacturing 955oC 1. Casting: The raw materials were calculated, weighrd and charged and processes melted in the induction furnace, then poured into the sand mould. After theof this specimen charges melting pouring casting annealing solidification, the casting was taken out from the mould for the next process.2. Annealing: Step 1.: Heating to 955oC, the temper carbon nucleus will be initiated. Step 2: Holding at 955oC: this step is called first-stage graphitization(FSG),massive carbides areeliminated from the iron structure. The soaking time may be about at least 48 hours. Then the casting is rapidly cooled to 740oC prior to entering the second-stage graphitization.Step 3: Slow cooling; the casting was slow cooled through the allotropic transformation range of the iron; this step is called second-stage graphitization(SSG), a completely ferritic matrix
free of pearlite and carbide is obtained.
Specimen nameFerrous Metal
ISO5922 AFNOR NF A32-702 BS 6681NETHERLANDS
NEN 6002-C
MaterialMalleable iron(annealed white cast iron)
Microstructures
P45-06 MN450-6 P45-06GSMp45
INTERNATIONAL FRANCE UK
Record of Microstructures
Photo.64:100x,Dark gray islands are tempered graphites. Purple and blue-green area areFerrite.
Photo.65:1000x, Same as in Photo.64, but in higher magnification. Dark gray islands aretempered graphite. The matrix is Ferrite. tempered graphite
44
500
Photo.66:500x, Same as in Photo.65, but in larger area. Dark gray islands are tempered graphite. Purple and blue-green area are Ferrite.ed graphiteFerrite
grain boundary
45
SpecimenNo.: 20
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 3.000-4.00 1.80-2.80 0.10-1.00 0.01-0.10 0.01-0.03 - - - - - - - -
Similar Germany SWEDEN JAPANsteels DIN 1693 SIS 1407 JIS G5502
GGG45 0722-00 FCD45Characteristics and applications: Nodular cast iron can be called Ductile cast iro or spheroidal graphite(SG) cast iron, it is cast iron in which the graphite is present as tiny spheres(nodules). The eutectic graphite separates from the molten iron during solidification and grows as spheres due to the additives introduced into the molten iron before casting.Some of the applications for nodular cast iron include: gears, high-fatigue strength application, high-impact application, automotive crankshafts, compreesor crankshafts, joints, etc.Heat Descriptions Processes Nitridingtreatment Temperature, oC 550-650guide Soaking time, min. 10-75 hrs.
Quenching medium furnace cool550-650HV
Manufacturing pro- Process: The charges (consist of pig iron, cast iron scraps, steel scraps, FeSi, FeMn, flux) werecess of this specimen charged into induction furnace and melted into liquid metal, then the molten metal was discharged into the
charge melting pouring casting crucible and then poured into the sand mould. Molten metal will be solidified into solid(casting). The casting was cut, mounted, ground, and polished to show graphite shapes, sizes and ditribution.
30HRC-80HRB
Austempering845-925
1hr./25 mm.+1 hr.oil or water45-58 HRC
air or faster
Microstructures
ASTM A536-8460-42-10
ISO 1083450-10
GOST7293VCh45
Tempering425-600
Hardness 163-217 HB 160-180 HB 45-58 HRCair or nitrogen furnace cool oil or water
1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 2 hrs min.510-565 870-900 845-925
FGS450-10 450/10
Normalizing Annealing Full hardening
USA FRANCE UKAFNOR NF A32201 BS 72892
INTERNATIONALRUSSIA
Specimen name Material ConditionFerrous Metal Nodular Cast Iron Annealed, un-etchedRecord of Microstructures
Photo.67:100x, Nodular cast iron, unetched, showing spheroidal graphites(dark brownparticles).
Photo.68:1000x, Same as in Photo.67, but in higher magnification. Dark gray island isspheroidal graphite.
graphite matrix
46
Photo.69:200x, Round particles are spheroidal graphites. The matrix can not be revealed in unetched condition.
47
SpecimenNo.: 21
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 3.00-4.00 1.80-2.80 0.10-1.00 0.01-0.10 0.01-0.03 - - - - - - - -
Similar Germany SWEDEN JAPANsteels DIN 1693 SIS 1407 JIS G5502
GGG45 0722-00 FCD45Characteristics and applications: Nodular can be called Ductile cast iron or spheroidal graphite(SG) cast iron, it is cast iron in which the graphite is present as tiny spheres(nodules). The eutectic graphite separates from the molten iron during solidification and grows as spheres due to the additives introduced into the molten iron before casting.Some of the applications for nodular cast iron include: gears, high-fatigue strength application, high-impact application, automotive crankshafts, compreesor crankshafts, joints, etc.Heat Descriptions Processes Nitridingtreatment Temperature, oC 550-650guide Soaking time, min. 10-75 hrs.
Quenching medium furnace cool550-650HV
Manufacturing pro- Process: The charges (consist of pig iron, cast iron scraps, steel scraps, FeSi, FeMn, flux) werecess of this specimen charged into induction furnace and melted into liquid metal, then the molten metal was discharged into the
charge melting pouring casting crucible and then poured into the sand mould. Molten metal will be solidified to solid(casting). The casting was cut, mounted, ground, and polished to show graphite and matrix.
Specimen name Material ConditionFerrous Metal Nodular Cast Iron Annealed, etched
UKASTM A536-84 AFNOR NF A32201 GOST7293 ISO 1083 BS 72892
USA FRANCE RUSSIA INTERNATIONAL
60-42-10 FGS450-10 VCh45 450-10
425-600
450/10
Normalizing Annealing Full hardening Tempering Austempering
air or faster
845-9251hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 1hr./25 mm.+1 hr. 2 hrs min. 1hr./25 mm.+1 hr.
510-565 870-900 845-925
oil or waterHardness 163-217 HB 160-180 HB 45-58 HRC 30HRC-80HRB 45-58 HRC
air or nitrogen furnace cool oil or water
Microstructures
Record of Microstructures
Photo.70:100x, Nodular cast iron, etched, brown round particles are spheroidal graphites. Thematrix are Ferrite(white, purple area), and Pearlite(brown islands).
Photo.71:1000x, Same as in Photo.70, but in higher magnification. Gray area is graphite.Purple and blue-green area are Ferrite.
FerritegraphitePearlite
graphiteFerrite
grain boundary
48
Photo.72:500x, Same as in Photo.71, but in larger area. The microstructures consist of spreroidal graphites, Pearlite and Ferrite. Bull's eyes structure can be seen in this Photo. ( Bull's structureconsists of graphit nodule in the center surrounded with Ferrite, and the outmost area is Pearlite. It looks like Bull's eyes.
Pearlite Ferrite
graphite
grainboundary
49
SpecimenNo.: 22
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 3.50 2.50 0.90 0.050 0.040 - 0.25 3.00 - - - - -
or BDI.Characteristics and applications: Bainitic Ductile Iron(BDI) is the high strength and wear resistant alloy cast iron. Microstructure of BDI consists of graphite nodulesand bainite as the matrix. BDI obtained through alloying during melting to produce bainite matrix which is hard and good wear resistant. Bainite matrix in BDI obtained in as cast conditionwithout any heat treatment. The applications of BDI are: gear, crank shafts, etc. Heat treatment:
Manufacturing Process: The charges (consist of pig iron, cast iron scraps, steel scraps, FeSi, FeMn, flux) wereprocess of this charged into induction furnace and melted into liquid metal, Ni, Mo, and inoculant were added during the specimen charge melting pouring casting process, the liquid metal was discharged into the crucible and then poured into the sand mould. The liquid
metal will solidify as the casting then cut, mounted, ground, polished, and etched for the examination.
Similar grade of BDI: The common name of this special cast iron is Bainitic Ductile Iron or BDI. Most foundries are also produce this kind of cast iron under the name Bainitic Ductile
Specimen name Material ConditionFerrous Metal Bainitic Ductile Iron(BDI) as cast
BDI may be tempered to adjust the hardness. The tempering temperature depends on the hardness required. The other heat treatment processes may not be required because the casting has been aalready hardened by alloying.
Microstructures
Record of Microstructures
Photo.73,100x, Bainitic Ductile Iron(BDI), etched, showing Bainite matrix and sphreoidal graphite. Photo.74:1000x, Same as in Photo.73, but in higher magnification. Brown round area is spheroidalgraphite surrounded with Bainite(purple,orange, blue-green, and brown area).
50
Photo.75:1000x, Same as in Photo.74, but in larger area. The microstructures consist of spheroidal graphites, and Bainite matrix. Some ferrite remained beside graphite.
51
SpecimenNo.: 23
Chemical C Si Mn P S Cr Mo Ni Cu Ti Co W Otherscomposition 2.00-3.30 1.50 max 2.00 max 0.10 max 0.06 max 23.00-30.00 3.00 max 2.50 max 1.20 max - - - -
Similarsteels
Characteristics and applications: This grade of cast iron is in the group of The high alloy white irons which are primarily used for abrasion-resistant applications and are readily cast in the shapes needed in the machinery used for crushing, griding, and general handling of abrasive materials. The eutectic carbides in the microstructures provided the high hardness needed for crushing and griding other materials. All high-alloy white irons contain chromium to prevent graphite formation and provide the stability of carbide phase.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Manufacturing pro- 1010 250 Processes: The raw material(pig iron, scraps,ferro-alloys,etc.) were chargedcess of this specimen
charge melting pouring casting full hardeningof the molud and heated to 1010oC and air cooled and tempered at 250oC.
** For heavy sections the rule of 1 hour per 25 mm. thickness
Microstructures
into the induction furnace for melting. Then the liquid metal was discharged and poured into the sand mould. After the solidification, the casting was taken out
Hardness - - - is usually adequate.
SIS 140466466
GermanyDIN 1695
G-X260Cr27; G-X300CrMo271
-80 to -196 1010-1020* 205 to 260
air air/oil air60 min./25 mm. thickness 3 to 4 hours minimum.** 3 to 4 hours minimum.*
3D
* Heavy sections usually require higher temperatures within the range.
Sub-zero treatment Full hardening Tempering Note:
Specimen name Material ConditionFerrous Metal Wear resistant cast iron As cast
USA FRANCE INDIABS 4844
IIIA:25% Cr FBCr26MoNiASTM A532 AFNOR NF A32-401 IS 4771-3
SWEDEN UK
HCr27/400
Record of Microstructures
Photo.76:100x, Wear resistant cast iron, etched. The structures are chromium carbides. Photo.77:1000x, Same as in Photo.76, but in higher magnification.
chromium carbide
52
Photo.78:500x, Same as in Photo.77, but in larger area. The structures are chromium carbides.
53
SpecimenNo.: 24
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 1.40-1.60 0.60 max 0.60 max 0.03 0.03 11.00-13.00 0.70-1.20 - 1.10 max - - - -
Similar CHINA SWEDEN JAPAN ITALY INDIAsteels AISI/SAE ASTM A681 DIN 17350 KRUPP GB 1299 SIS14 JISG4404 UNI2955 IS 3749
D2 D2 1.2379 2379 3-2Cr12MoV 2310 SKD11 DCT-AR T160Cr12Characteristics and applications: Most available and most popular of the D series tool steels. Deep hardening, with low distorsion and high safety in weldability.resistant to softening and medium resistant to decarburization. Readily nitrided. D2 steel is air hardening and attain full hardness when cooled in still air. D2 steel contain massive amount of carbides, which make it susceptible to edge brittleness. Typical applications of D2 steel include long run dies for blanking, forming,thread rolling, deep drawing, slitter knives, etc.Heat Descriptions Processes Tempering Nitridingtreatment Temperature, oC 205-540 500guide Soaking time, min. 2 hrs min. 10-75 hrs.
Quenching medium air furnace cool61- 54 HRC >750 HV
Final heat treatment oC 880 furnace cool Process: The specimen is heated to 880oC for 90 min., the steel microstructures will transform toprocess of this preheat 815 90 austenite, then cool down slowly in the furnace, austenite will transform to ferrite and pearlite. The steel specimen 30 min. min. will be softened,better machinability,better cold workability,and improve dimensional stability,etc.
Specimen name Material ConditionFerrous Metal High C-High Cr Tool steel(AISI D2) Annealed
USA GERMANY UKBS 4659
FRANCEAFNOR NF A35-590
BD2
Normalizing Annealing Stress relieving
90 min./inch of thickness 60 min./inch of thicknessDo not normalize 870 - 900 675-705 Pre:815;Aus:980-1025
furnace cool airHardness 217-255 HB -
Z160CDV 12
Hardening
air or nitrogen gas62 to 64 HRC
15 min.(small);45 min.(large)
Microstructures
Record of Microstructures
Photo.79:100x, AISI D2 Tool steel, annealed. Microstructures consist of Ferrite matrixand Carbides.
Photo.80:1000x, Same as in Photo.79, but in higher magnification. Ferrite matrix iscolred greenand brown, Carbides remained bright particles.
54
200
Photo.81:1000x, Same as in Photo.80, but in larger area, showing the distribution of Carbides in Ferrite matrix.
55
SpecimenNo.: 25
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 1.40-1.60 0.60 max 0.60 max 0.03 0.03 11.00-13.00 0.70-1.20 - 1.10 max - - - -
Similar CHINA SWEDEN JAPAN ITALY INDIAsteels AISI/SAE ASTM A681 DIN 17350 KRUPP GB 1299 SIS14 JISG4404 UNI2955 IS 3749
D2 D2 1.2379 2379 3-2Cr12MoV 2310 SKD11 DCT-AR T160Cr12Characteristics and applications: Most available and most popular of the D series tool steels. Deep hardening, with low distorsion and high safety in weldability.resistant to softening and medium resistant to decarburization. Readily nitrided. D2 steel is air hardening and attain full hardness when cooled in still air. D2 steel contain massive amount of carbides, which make it susceptible to edge brittleness. Typical applications of D2 steel include long run dies for blanking, forming,thread rolling, deep drawing, slitter knives, etc.Heat Descriptions Processes Tempering Nitridingtreatment Temperature, oC 205-540 500guide Soaking time, min. 2 hrs min. 10-75 hrs.
Quenching medium air furnace cool61- 54 HRC >750 HV
Final heat treatment oC 1025 Process: The specimen is heated to 1025oC for 90 min., the steel microstructures will transform toprocess of this preheat 815 90 520 520 austenite, then quench in nitrogen gas(in vacuum furnace), austenite will transform to martensite and specimen 30 min. min. then temper immediately at 520oC after the specimen has cooled to about 50oC, Double temper.
USA GERMANY FRANCE
Quenched and temperedCondition
UKAFNOR NF A35-590 BS 4659
Specimen name MaterialFerrous Metal High C-High Cr Tool steel(AISI D2)
Z160CDV 12 BD2
Normalizing Annealing Stress relieving HardeningDo not normalize 870 - 900 675-705 Pre:815;Aus:980-1025
90 min./inch of thickness 60 min./inch of thickness 15 min.(small);45 min.(large)furnace cool air air or nitrogen gas
Hardness 217-255 HB - 62 to 64 HRC
Microstructures
Record of Microstructures
Photo.82:100x, AISI D2 Tool steel, quenched and tempered. Microstuctures consist ofMartensite and Carbides.
Photo.83:1000x, Same as in Photo.82, but in higher magnification. Martensite tintedvariuos colors. Carbides remained bright particles.
56
Photo.84:1000x, Same as in Photo.83, but in larger area. The matrix is Martensite tinted various colors, and bright particles are carbides.
57
SpecimenNo.: 26
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.10 max 0.10-0.40 0.10-0.40 0.025 max 0.025 max 0.75-1.25 0.15-0.40 0.10-0.50 - - - - -
Similar RUSSIA UKsteels AISI/SAE ASTM A681 DIN KRUPP SS14 ASSAB DAIDO HITACHI N.KOSHUHA GOST BS4659
P20 P20 1.2311 2311 USA P20 718Supreme PX 4 YSS: HPM 2 Plasmold20 4ChS USA P20Characteristics and applications: Mold steel AISI P20 normally is supplied heat treated to 30-36 HRC, a condition in which it can be machined readily into large, intricate dies and molds. Because this steel is prehardened, no subsequench high temperature heat treatment is required, and distortion and size changes are avoided. However, when used for plastic mold, type P20 is sometimes carburized and hardened after the immpression has been machined. Most application is for plastic mold making.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Final heat treatment oC 780 furnace cool Process: The specimen is heated to 780oC for 60 min., the steel microstructures will transform toprocess of this preheat 815 60 austenite, then cool down slowly in the furnace, austenite will transform to ferrite and pearlite. The steel specimen 30 min. min. will be softened, better machinability, better cold workability, and improve dimensional stability,etc.
AnnealedSpecimen name Material Condition
Ferrous Metal Mould tool steel ( AISI P20)
USA GERMANY FRANCEAFNOR NF A35-590
35CM7D
Normalizing Annealing Stress relieving Hardening900 760-790 650-675 Carburize:920, Harden: 815-870
oil60 min./inch of thickness 60 min./inch of thickness 60 min./inch of thickness Carburize:to case depth;Harden:15 min
149-179 HB 149-212 HB -air furnace cool air
60 to 64 HRC
Microstructures
SWEDEN JAPAN
TemperingCarburized mold:175-230
2 hrs min.air
62- 58 HRCHardness
Record of Microstructures
Photo.85:100x, AISI P20 Mold Tool steel, annealed. Microstructures consist of Ferriteand Carbides. Black dots are porosities.
Photo.86:1000x, Same as in Photo.85, but in higher magnification.Blue-green area are Ferrite.Bright particles are Carbides.
58
Photo.87:1000x, Same as in Photo.86, but in larger area.
59
SpecimenNo.: 27
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.10 max 0.10-0.40 0.10-0.40 0.025 max 0.025 max 0.75-1.25 0.15-0.40 0.10-0.50 - - - - -
Similar RUSSIA UKsteels AISI/SAE ASTM A681 DIN KRUPP SS14 ASSAB DAIDO HITACHI N.KOSHUHA GOST BS4659
P20 P20 1.2311 2311 USA P20 718Supreme PX 4 YSS: HPM 2 Plasmold20 4ChS USA P20Characteristics and applications: Mold steel AISI P20 normally is supplied heat treated to 30-36 HRC, a condition in which it can be machined readily into large, intricate dies and molds. Because this steel is prehardened, no subsequench high temperature heat treatment is required, and distortion and size changes are avoided. However, when used for plastic mold, type P20 is sometimes carburized and hardened after the immpression has been machined. Most application is for plastic mold making.Heat Descriptions Processestreatment Temperature, oCguide Soaking time, min.
Quenching medium
Final heat treatment oC 850 Process: The specimen is heated to 850oC for 15 min., the steel microstructures will transform toprocess of this preheat 600 15 300 300 austenite, then quench in oil, austenite will transform to martensite. Then temper at 300oC for 120 min. specimen 30 min. min. The microstructure will be tempered martensite. Double temper.
SWEDEN JAPANUSA GERMANY FRANCE
Material ConditionFerrous Metal Mould tool steel ( AISI P20) Quenched and tempered
Specimen name
AFNOR NF A35-59035CM7D
Normalizing Annealing Stress relieving Hardening Tempering900 760-790 650-675 Carburize:920, Harden: 815-870 Carburized mold:175-230
2 hrs min.air furnace cool air oil air
60 min./inch of thickness 60 min./inch of thickness 60 min./inch of thickness Carburize:to case depth;Harden:15 min
Hardness 149-179 HB 149-212 HB - 60 to 64 HRC 62- 58 HRC
Microstructures
Record of Microstructures
Photo.88:100x, Microstructures consist of tempered Martensite and some inclusions Photo.89:1000x, Same as in Photo.88, but in higher magnification. Martensite is clearlyseen in brown and gray.
60
Photo.90:1000x, Same as in Photo.88, but in larger area. The strucutre is tempered martensite.
61
SpecimenNo.: 28
Chemical C Si Mn P S Cr Mo Ni V Ti Co W Otherscomposition 0.95-1.05 0.20-0.45 0.15-0.40 0.03 max 0.003 max 3.75-4.5 4.50-6.75 0.30 max 2.25-2.75 - - 5.00-6.75 -
Similar RUSSIA UKsteels AISI/SAE ASTM A600 DIN Bohler SS14 ASSAB JIS G4403 HITACHI N.KOSHUHA GOST BS4659
M2 M2 high C 1.3345 S600 2722 ASP-41 SKH 51 YXM 1 H 51 R6M5 BM2Characteristics and applications: M2 is the most widely used high speed steel suitble for a multitude of applications and available with several carbon contents. M2 is very high in resistance to wear and to softening at elevated temperature. It rates low in toughness, but using a lower austenitizing temperature with the resulting slightly lower hardnessimproves its impact resistance. Mostly M2 is used for various cutting tools e.g. hack saw blades, drills, taps, cutters, single point cutting tools, etc.Heat Descriptions Processes Temperingtreatment Temperature, oC 540-595guide Soaking time, min. 120
Quenching medium air65-60
Final heat treatment oC 850 1190 Process: The specimen was double preheat at 650 and 850 oC and austenitized at 1190oC for 15 min.process of this preheat 650 15 590 590 590 in vacuum furnace. Then nitrogen quenched and triple temper at least 120 min. each for soaking time. Thespecimen 30 min. min. final microstructures will be tempered martensite and carbides.
Specimen name Material ConditionFerrous Metal High Speed Steel (AISI M2) Quenched and tempered
USA GERMANY FRANCE SWEDEN
Do not normalize 870-900 650-675
JAPANAFNOR NF A35-590
4301 6-5-2
Normalizing Annealing Stress relieving
furnace cool air60 min./inch of thickness 60 min./inch of thickness
Microstructures
HardeningDouble preheat:650/850;Austenitize:1190-1230
15Nitrogen quench in vacuum furnace
64-66 HRCHardness 212-241 HB -
Record of Microstructures
Photo.91:100x, High speed steel, quenched and tempered. Microstructures consist ofMartensite and Carbides.
Photo.92:1000x, Same as in Photo. 91, but in higher magnification. Brown and dark graybackground are Martensite. Light brown particles are Carbides.
62
Photo.93:1000x, Same as in Photo. 92, but in larger area. Microstructures consist of Martensite(brown and dark gray needle structures), and carbides(light brown round andelongated particles).
63
SpecimenNo.: 29
Chemical C Si Mn P S Cr Mo Ni V Ti Cu W Otherscomposition 1.268 0.525 13.38 0.042 0.004 2.105 0.094 0.074 0.023 0.029 0.368 - -
Similar USA AUSTRALIA GERMANY ITALY ROMANIAsteels ASTM A128 AS 2074 DIN UNI 3160 STAS3718
A H19 1.3802 GX120Mn12 T105Mn120Characteristics and applications: The original austenitic manganese steel, containing about 1.2%C and 12%Mn, was invented by Sir Robert Hadfield in 1882.It combined high toughness and ductility with high-hardening capacity and excellent resistance to wear. It is still used extensively, with composition and heat treatment modification, prima-rily in the fields of earthmoving, mining, quarrying, oil well drilling, railroading,and in the manufacture of cement and clay products.Example:rock crusher, bucket,wear plate, etc.Manufacturing Process: The charges (consist of pig iron, cast iron scraps, steel scraps, FeSi, FeMn, flux) wereprocess of this charged into induction furnace and melted into liquid metal, Fe-Mn was added during the melting process. specimen charge melting pouring casting The liquid metal was discharged into the crucible and then poured into the sand mould. The liquid metal
will solidify as the casting then cut, mounted, ground, polished, and etched for the examination.
UK
BW10(En 1457)
SPAIN
AM-X-120Mn12UNE 36253 BS3100G5131
SCMnH3MNC 720E
2183
MaterialHigh manganese steel
ConditionAs cast
Specimen nameFerrous Metal
Microstructures
JAPAN MEXICO
Record of Microstructures
Photo.94:50x, High-Manganese steel casting, as cast. Microstructure are Austenite. Whiteparticles along grain boundaries and in the Austenite grains are Carbides.
Photo. 95:1000x, Same as in Photo. 94, but in higher magnification. Austenite grains aretinted various colors. Carbides along grain boundaries are colored light purple.
64
1000
Photo. 96:200x, Same as in Photo. 95, but in larger area. Austenite grains are tinted various colors. Carbides are shown along grain boundaries and in Austenite grains.
grain boundarywith carbides
Carbide
inclusion
Austenite65
SpecimenNo.: 30
Chemical C Si Mn P S Cr Mo Ni V Ti Cu W Otherscomposition 1.268 0.525 13.38 0.042 0.004 2.105 0.094 0.074 0.023 0.029 0.368 - -
Similar USA AUSTRALIA GERMANY ITALY ROMANIAsteels ASTM A128 AS 2074 DIN UNI 3160 STAS3718
A H19 1.3802 GX120Mn12 T105Mn120Characteristics and applications: The original austenitic manganese steel, containing about 1.2%C and 12%Mn, was invented by Sir Robert Hadfield in 1882.It combined high toughness and ductility with high-hardening capacity and excellent resistance to wear. It is still used extensively, with composition and heat treatment modification, prima-rily in the fields of earthmoving, mining, quarrying, oil well drilling, railroading,and in the manufacture of cement and clay products.Example:rock crusher, bucket,wear plate, etc.Heat treatment guide: Heat treatment strengthens austenitic manganese steel so that it can be used safely and reliably in variety of engineering applications.Solution annealing and quenching are the standard processes.
Manufacturing pro- 1050 water Processes: The raw material(pig iron, scraps,ferro alloy, etc.) were chargedcess of this specimen
charge melting pouring castingof the mold and heated to 1050oC and quench in water.
into the induction furnace for melting. Then the liquid metal was discharged and poured into the sand mould. After the solidification, the casting was taken out
Solution annealing and quenchingTemerature,oCSoaking timeQuenchant
1010-10901 to 2 hours per 25 mm. of thickness
agitated water
UNE 36253 BS3100SCMnH3 2183 AM-X-120Mn12 BW10(En 1457)
SPAIN UK
Specimen name Material ConditionFerrous Metal High manganese steel Solution annealed
G5131 MNC 720EJAPAN MEXICO
Microstructures
Record of Microstructures
Photo.97:50x, High Manganese Steel casting, annealed. Microstructures are Austenite.The purple area shows the trace of dendrite.
Photo.98:1000x, Same as in Photo. 97, but in higher magnification. The carbide alonggrain boundaries decreased after annealing.
Carbides remained alonggrain boundary
66
Photo.99:200x, Same as in Photo. 98, but in larger area. The microstructures are Austenite. The grain boundaries are thinner and less carbide after annealing.
Austenite grain boundary
Carbide
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